Endothelin-induced constriction of guinea pig airways: role of platelet-activating factor.
Endothelin-1 (ET-1, 1-100 nM) evoked a concentration-dependent contraction of guinea pig trachea and upper bronchi in vitro. The response was significantly attenuated by BN 52021 (ginkgolide B, 10 microM), a specific receptor antagonist to platelet-activating factor. Precontraction of the tissues with endothelin (50 nM) desensitized tissues to platelet-activating factor (200 nM), while preincubation of the tissues with platelet-activating factor slightly inhibited the response to endothelin. These findings suggest that platelet-activating factor may mediate endothelin-induced airway contraction in the guinea pig.
Battistini
B
B
Department of Pharmacology, Faculty of Medicine, University of Sherbrooke, P.Q., Canada.
Sirois
P
P
Braquet
P
P
Filep
J G
JG
D000818:Animals; D016084:Bronchoconstriction / Q000187:drug effects*; D004224:Diterpenes; D016232:Endothelins / Q000494:pharmacology*; D046934:Ginkgolides; D006168:Guinea Pigs; D006632:Histamine / Q000494:pharmacology; D066298:In Vitro Techniques; D007783:Lactones / Q000494:pharmacology; D008297:Male; D009130:Muscle, Smooth / Q000187:drug effects; D010972:Platelet Activating Factor / Q000037:antagonists & inhibitors / Q000502:physiology*; D014132:Trachea / Q000187:drug effects*
D004224:Diterpenes; D016232:Endothelins; D046934:Ginkgolides; D007783:Lactones; D010972:Platelet Activating Factor; D006632:Histamine; C045856:ginkgolide B